Method of kelvin current sense in a semiconductor package

ABSTRACT

Regulating a direct current-to-direct current (DC-DC) converter, a semiconductor switch having an improved current sensing technique is used to switch a DC voltage input at a predefined frequency. The switch includes a control pin to receive a control signal for controlling a current flowing between an input pin and an output pin. The switch also includes a Kelvin sense pin electrically coupled to an output pad located on a semiconductor die of the device for sensing the current. An electrical path from the output pad to the output pin in the form of a conductive lead wire has a predefined resistance. The current is Kelvin current sensed using the predefined resistance to tightly control deviation in the current beyond a predefined range.

BACKGROUND

The present disclosure relates to the field of power supplies, and moreparticularly to methods and systems for improving regulation efficiencyof a direct current-to-direct current (DC-DC) converter included in aninformation handling system.

As the value and use of information continues to increase, individualsand businesses seek additional ways to acquire, process and storeinformation. One option available to users is information handlingsystems. An information handling system (‘IHS’) generally processes,compiles, stores, and/or communicates information or data for business,personal, or other purposes thereby allowing users to take advantage ofthe value of the information. Because technology and informationhandling needs and requirements vary between different users orapplications, information handling systems may also vary regarding whatinformation is handled, how the information is handled, how muchinformation is processed, stored, or communicated, and how quickly andefficiently the information may be processed, stored, or communicated.The variations in information handling systems allow for informationhandling systems to be general or configured for a specific user orspecific use such as financial transaction processing, airlinereservations, enterprise data storage, entertainment, and/or globalcommunications. In addition, information handling systems may include avariety of hardware and software components that may be configured toprocess, store, and communicate information and may include one or morecomputer systems, data storage systems, and networking systems.

Presently, many DC-DC converters provide over current protection (OCP)by sensing the voltage across the synchronous rectifier (low sideswitch) and comparing the voltage to a maximum value. Since the voltageis proportional to the current flowing through the switch, a need for aseparate current sense resistor is often eliminated.

However, the proportionality factor that defines the relationshipbetween the voltage and the current is dependent on the switchparameters such as on resistance. Typically, a value of the onresistance has a large degree of variance with respect to a nominal orrated value since it is dependent on semiconductor material properties,which may vary with each production run. That is, the value of onresistance may vary significantly, e.g., 100% variation, compared to therated value, thereby causing a large variation in the current. Forexample, if an OCP set point is defined to be 110% of the rated currentvalue, the actual value of current at which the OCP is triggered mayvary from 110% of rated current and 220% of the rated current. Adoptionof best design practices may result in the selection of an inductorcapable of carrying 220% of the rated current, often resulting inincreased cost and space. Failure to select a properly rated inductormay cause an undetected over current condition, thereby increasinginductor saturation, resulting in over voltage and causing possibledamage to a load connected to the DC-DC converter.

Therefore, a need exists for regulating a DC-DC converter of a powersupply. More specifically, a need exists to provide a DC-DC converterhaving an improved current sensing technique that provides a narrowerrange of variance in OCP set points. Accordingly, it would be desirableto provide for a more efficient and reliable power supply included in anIHS, absent the disadvantages found in the prior methods discussedabove.

SUMMARY

The foregoing need is addressed by the teachings of the presentdisclosure, which relates to providing over current protection in apower supply. Accordingly, one embodiment provides for sensing currentflowing through a semiconductor device including selecting a portion ofa current path within the semiconductor device. The selected portion ofthe current path is in the form of a conductive lead wire from a Kelvinsense pin of the device to the output pin of the device. The conductivelead wire has a predefined resistance that is independent ofsemiconductor properties of the semiconductor device. The current issensed by measuring voltage across the conductive lead wire.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a block diagram of an information handling systemhaving an improved power supply, according to an embodiment.

FIG. 2 is a block diagram illustrating additional details of a directcurrent-to-direct current (DC-DC) converter described with reference toFIG. 1, according to an embodiment.

FIG. 3 is a schematic diagram illustrating additional details of asemiconductor switch described with reference to FIG. 2, according to anembodiment.

FIG. 4A illustrates a pin/pad layout arrangement for a semiconductordevice packaged as a small outline integrated circuit, according to anembodiment.

FIG. 4B illustrates a pin/pad layout arrangement for a semiconductordevice packaged as a flip-leaded molded package (FLMP), according to anembodiment.

FIG. 5 is a flow chart illustrating a method for sensing current flowingthrough a semiconductor device, according to an embodiment.

DETAILED DESCRIPTION

Novel features believed characteristic of the present disclosure are setforth in the appended claims. The disclosure itself, however, as well asa preferred mode of use, various objectives and advantages thereof, willbest be understood by reference to the following detailed description ofan illustrative embodiment when read in conjunction with theaccompanying drawings. The functionality of various circuits, devices,boards, cards, modules, blocks, and/or components described herein maybe implemented as hardware (including discrete components, integratedcircuits and systems-on-a-chip ‘SOC’), firmware (including applicationspecific integrated circuits and programmable chips) and/or software ora combination thereof, depending on the application requirements.

For purposes of this disclosure, an IHS may include any instrumentalityor aggregate of instrumentalities operable to compute, classify,process, transmit, receive, retrieve, originate, switch, store, display,manifest, detect, record, reproduce, handle, or utilize any form ofinformation, intelligence, or data for business, scientific, control, orother purposes. For example, the IHS may be a personal computer,including notebook computers, personal digital assistants, cellularphones, gaming consoles, a network storage device, or any other suitabledevice and may vary in size, shape, performance, functionality, andprice. The information handling system may include random access memory(RAM), one or more processing resources such as central processing unit(CPU) or hardware or software control logic, ROM, and/or other types ofnonvolatile memory. Additional components of the information handlingsystem may include one or more disk drives, one or more network portsfor communicating with external devices as well as various input andoutput (I/O) devices, such as a keyboard, a mouse, and a video display.The information handling system may also include one or more busesoperable to receive/transmit communications between the various hardwarecomponents.

FIG. 1 illustrates a block diagram of an information handling system 100having an improved power supply, according to an embodiment. Theinformation handling system 100 includes a processor 110, a systemrandom access memory (RAM) 120 (also referred to as main memory), anon-volatile read only memory (ROM) 122 memory, a display device 105, akeyboard 125 and an I/O controller 140 for controlling various otherinput/output devices. For example, the I/O controller 140 may include akeyboard controller, a cursor device controller and/or the serial I/Ocontroller. It should be understood that the term “information handlingsystem” is intended to encompass any device having a processor thatexecutes instructions from a memory medium.

The IHS 100 is shown to include a hard disk drive 130 connected to theprocessor 110, although some embodiments may not include the hard diskdrive 130. In a particular embodiment, the IHS 100 may includeadditional hard disks. The processor 110 communicates with the systemcomponents via a bus 150, which includes data, address and controllines. In one embodiment, the IHS 100 may include multiple instances ofthe bus 150. A communications device 145, such as a network interfacecard and/or a radio device, may be connected to the bus 150 to enablewired and/or wireless information exchange between the IHS 100 and otherdevices (not shown).

In a particular embodiment, the IHS 100 receives power from a powersupply system 170 having a direct current-to-direct current (DC-DC)converter 180. The power supply system 170 receives an alternatingcurrent (AC) input 172 such as 110/120 volts from an electrical walloutlet. The DC-DC converter 180 provides a regulated DC output 182 to aload. The load may include one or more components of the IHS 100 such asthe processor 110. Additional detail of the DC-DC converter 180 havingan improved current sensing technique is described with reference toFIG. 2.

The processor 110 is operable to execute the computing instructionsand/or operations of the IHS 100. The memory medium, e.g., RAM 120,preferably stores instructions (also known as a “software program”) forimplementing various embodiments of a method in accordance with thepresent disclosure. An operating system (OS) of the IHS 100 is a type ofsoftware program that controls execution of other software programs,referred to as application software programs. In various embodiments theinstructions and/or software programs may be implemented in variousways, including procedure-based techniques, component-based techniques,and/or object-oriented techniques, among others. Specific examplesinclude assembler, C, XML, C++objects, Java and Microsoft's .NETtechnology.

FIG. 2 is a block diagram illustrating additional details of a directcurrent-to-direct current (DC-DC) converter described with reference toFIG. 1, according to an embodiment. The DC-DC converter 200 is operableto receive a direct current (DC) voltage input 205 and generate aregulated DC voltage output 295. In one embodiment, the regulated DCvoltage output 295 provides power to a load 290 such as the processor110. The output 295 may also be used to power other components (notshown) included in the IHS 100. In a particular embodiment, the DC-DCconverter 200 is substantially the same as the DC-DC converter 180 andthe regulated DC voltage output 295 is substantially the same as theregulated DC output 182 described with reference to FIG. 1.

In the depicted embodiment, the DC-DC converter 200 includes:

a) a controller module 210 operable to receive a plurality of feedbackinputs 208 such as the regulated DC voltage output 295 and currents tocontrol a duty cycle;

b) a high-side switch 220 operable to receive the DC voltage input 205and generate a switched DC voltage output 225 in response to receiving acontrol signal 212 from the controller module 210;

c) a low-side switch 230 electrically coupled in-between the switched DCvoltage output 225 and a predefined voltage reference such as a ground218. The operation of the low-side switch 230 is complementary to thatof the high-side switch 220 and is controlled by a control signal 214generated by the controller module 210. That is, the high-side switch220 is closed when and low-side switch 230 is open and vice versa; and

d) a filter module 240 electrically coupled in parallel to the low-sideswitch 230 to filter out alternating current (AC) components from theswitched DC voltage output 225 and generate the regulated DC voltageoutput 295.

The DC voltage input 205 is generated by an AC/DC adapter (not shown)included in the power supply system 170, which provides power to theload 290. The load 290 may be one or more components of the IHS 100.During a charge cycle the high-side switch 220 is closed and thelow-side switch 230 is open. During a discharge cycle the high-sideswitch 220 is open and the low-side switch 230 is closed. The openingand closing of the high-side and low-side switches 220 and 230 iscontrolled by the control signals 212 and 214 respectively. The DCvoltage input 205 is “chopped” by the high-side switch 220 to generatethe switched DC voltage output 225. The switched DC voltage output 225may be a square wave having a predefined switching frequency. The squarewave, which has several AC components, has an average voltage equal tothe required output voltage. It is understood that each one of thehigh-side switch 220 and the low-side switch 230 may be implemented as asemiconductor switch. Examples of a semiconductor switch may include thebipolar junction transistor (BJT), the insulated gate bipolar transistor(IGBT), the metal-oxide semiconductor field effect transistor (MOSFET),thyristors such as a gate turn-off thyristor (GTO), a mosfet controlledthyristor (MCT), a silicon controlled rectifier (SCR), a junction fieldeffect transistor (JFET) and similar others.

In one embodiment, the filter module 240 includes an inductance L 242and a capacitor C 244. The filter module 240 filters the predefinedswitching frequency from the switched DC voltage output 225 andgenerates the regulated DC voltage output 295. The inductance L 242 andcapacitor C 244 values may be selected based on factors such as thepredefined switching frequency, maximum allowable current flowingthrough the load 290 and similar others.

Duty cycle is generally indicative of time during which a device and/orsystem is operated. Thus, the duty cycle of the DC-DC converter 200 maybe expressed as a ratio or percentage of an ON period to the total(ON+OFF) period. The control signals 212 and 214 control a duration ofan ON and an OFF state of each one of the switches 220 and 230, therebycontrolling the duty cycle of the DC-DC converter 200. Although theDC-DC converter 200 is shown to include a single phase it may optionallyinclude additional phases to further reduce the voltage ripple.

In a particular embodiment, the controller module 210 monitors voltageacross a selective portion of a current path within the low-side switch230. By having known values for the voltage and for a predefinedresistance value for the selective portion of the current path, acurrent value is derived using Ohms law. Thus, the controller module 210is operable to monitor and control occurrence of an over currentcondition. That is, if the controller module 210 detects voltage acrossthe selective portion to be greater than a predefined threshold then thecontrol signal 212 is maintained in the de-asserted state to disable theflow of current. In a particular embodiment, the low-side switch 230 isa semiconductor device such as a MOSFET switch having the predefinedresistance value for the selective portion of the current path.Additional details of the current sensing technique using the selectiveportion of the current path within the low-side switch 230 are describedwith reference to FIG. 3.

FIG. 3 is a schematic diagram illustrating additional details of asemiconductor switch described with reference to FIG. 2, according to anembodiment. In the depicted embodiment, the low-side switch 230described with reference to FIG. 2 is implemented as a semiconductordevice 300 having an input pin 310, a control pin 320, an output pin 330and a Kelvin sense pin 340. In a particular embodiment, the input pin310 is a drain pin, the control pin 320 is a gate pin and the output pin330 is a source pin of a semiconductor switch. In another embodiment,the input pin 310 may be a source pin, the control pin 320 may be a gatepin and the output pin 330 may be a drain pin of another semiconductorswitch. Thus, it is understood that the input/output functions mayreverse depending on choice of p-channel or n-channel semiconductorswitches. In the depicted embodiment, the input pin 310 receives aninput 312 such as the switched DC voltage output 225. The output pin 330is coupled to a predefined voltage output such as the ground 218. Thecontrol pin 320 receives a control signal 322 such as the control signal214. The conductive, e.g., ON state and the non-conductive, e.g., OFFstate, of the semiconductor device 300 is controlled by asserting orde-asserting the control signal 322. Thus, the control signal 322controls a flow of current between the output pin 330 and the input pin310. Additional details of package layout arrangements for the pins 310,320, 330 and 340 are described with reference to FIG. 4A and 4B.

The ON state resistance (or the internal resistance) of thesemiconductor device 300 is dependent on properties of the semiconductormaterial used to manufacture the device. The on resistance is computedby equation 100 as follows:R(on resistance)=R _(source) +R _(ch) +R _(A) +R _(J) +R _(D) +R _(sub)+R _(cum)  Equation 100where R_(source) is source diffusion resistance, R_(ch) is channelresistance, R_(A) is accumulation resistance, R_(J) is JFET componentresistance of the region between the two body regions, R_(D) is thedrift region resistance, R_(sub) is the substrate resistance and R_(cum)is the cumulative conductive path resistance between the output pin 330and the input pin 310. The cumulative conductive path resistance mayinclude bond wire resistance, the contact resistance between the sourceand drain metallization and the silicon, metallization and leadframecontributions. Thus, due to the dependence of on resistance onsemiconductor properties, a value of the on resistance may varysignificantly compared to a rated or nominal value.

In the ON state, the current path within the semiconductor device 300includes the input pin 310, a semiconductor channel (not shown), theKelvin sense pin 340 and the output pin 330. In the depicted embodiment,resistance of the conductive path between an output pad 342 located on asemiconductor die of the device 300 and the output pin 330 is known,e.g., may be derived based on length, diameter and type of conductivematerial. Since the resistance of the conductive path is known and isrelatively independent of the semiconductor properties of thesemiconductor device 300, there is less variation in a value of theresistance of the conductive path compared to the variation in the valueof on resistance. In a particular embodiment, a lesser variation in theresistance of the conductive path provides a more accurate determinationof the current value compared to the accuracy provided by on resistancebased current sense technique.

In high current, low resistance applications, a Kelvin current sensingtechnique typically uses separate wiring paths for the current-carryingcircuits and the measurement circuits. The Kelvin sensing or measurementtechnique uses four-wire measurements. Many low-value precisionresistors have four terminals—two for carrying current and two formeasuring the voltage across the resistance element. However, four-wireresistors may be unavailable in low cost integrated circuit (IC) packageform. If low cost four wire resistors may not be available, two-wirecomponents may be used along with using a Kelvin-connectionpc-board-layout technique. The Kelvin connection pc-board layouttechnique (also referred to as a force and sense technique)substantially prevents circuit board trace resistance from adding to thevalue of the resistor.

As described earlier, current flowing through the semiconductor device300 is sensed and/or measured by performing a Kelvin current senseacross the conductive path between the output pad 342 located on asemiconductor die of the device 300 and the output pin 330 having thepredefined resistance. The Kelvin sense pin 340 is coupled to the outputpad 342. For DC signals, the output pad 342 and the Kelvin sense pin 340may be equivalent. However, they may not be considered to be equivalentacross a frequency range of interest due to the impedance of the KelvinSense interconnect. Majority of the current flows through the output pin330 and the output pad 342, while lesser current flows through theKelvin sense pin 340. In a particular embodiment, a comparator 350 isused to compute a voltage difference 352 between the output pad 342 andthe output pin 330. In a particular embodiment, the comparator 350 is adifferential amplifier. Since the resistance of the conductive pathbetween the output pad 342 and the output pin 330 is known, a value ofthe current is computed based on the measured voltage difference 352. Ina particular embodiment, the voltage difference 352 is provided to thecontroller 210 as one of the plurality of feedback inputs 208. If thevoltage difference 352 exceeds a predefined threshold, e.g., 150% ofrated value, the controller 210 de-asserts the control signal 212 toturn OFF the high-side switch 220, thereby interrupting the flow ofcurrent through the device to provide OCP. In an embodiment, the controlsignal 214 may be asserted to latch on the low-side switch 230.

In an exemplary, non-depicted embodiment, the Kelvin sense pin 340 maybe coupled to an input pad (not shown) located on the semiconductor dieof a device and the input pin 310. In this embodiment, the currentflowing through the semiconductor device 300 is sensed and/or measuredby performing a Kelvin current sense across the conductive path betweenthe input pad and the input pin 310 having the predefined resistance.

FIG. 4A illustrates a pin/pad layout arrangement for a semiconductordevice packaged as a small outline integrated circuit, according to anembodiment. In the depicted embodiment, the semiconductor device 300described with reference to FIG. 3 is implemented as a small outline(SO) integrated circuit (IC) having 9 pins/pads. In a particularembodiment, a standard 8 pin switch S08 IC may be modified by adding a9_(th) pin/pad for the Kelvin sensing. In the depicted embodiment, theoutput pin 330 is configured by electrically coupling a plurality ofpins/pads 412, 414, 416 and 418. The control pin 320 is substantiallythe same as pin/pad 402. The input pin 310 is configured by electricallycoupling a plurality of pins/pads 404, 406, and 408. The Kelvin sensepin 340 is substantially the same as a 9_(th) pin/pad 410. Currentflowing through the semiconductor device 300 is sensed by performing aKelvin current sense measurement across the conductive path between thepin/pad 410 and the pins/pads 404, 406, 408.

FIG. 4B illustrates a pin/pad layout arrangement for a semiconductordevice packaged as a flip-leaded molded package (FLMP), according to anembodiment. In the depicted embodiment, the semiconductor device 300described with reference to FIG. 3 is implemented as flip-leaded moldedpackage (FLMP) integrated circuit (IC) having 6 pins/pads. In aparticular embodiment, a standard 5 pin/pad switch FLMP IC may bemodified by adding a 6^(th) pin/pad for the Kelvin sensing. In thedepicted embodiment, the output pin 330 is substantially the same as pin432. The control pin 320 is substantially the same as pin/pad 422. Theinput pin 310 is configured by electrically coupling a plurality ofpins/pads 424, 426 and 428. The Kelvin sense pin 340 is substantiallythe same as a 6^(th) pin 430. In a particular embodiment, the standard 5pin FLMP is modified by selecting a portion of the output pin as theKelvin sense pin 430. Current flowing through the semiconductor device300 is sensed by performing a Kelvin current sense measurement acrossthe conductive path between the pin 430 and the pins 424, 426, 428.

Although FIG.'s 4A and 4B describe two types of packaging for thesemiconductor device 300, it is contemplated that the semiconductordevice 300 may be packaged in a variety of alternative packaging formssuch as dual-in-line (ceramic), dual-in-line (plastic), thin smalloutline package (TSOP), discrete packaging (DPAK, D2PAK and IPAK) andsimilar others.

FIG. 5 is a flow chart illustrating a method for sensing current flowingthrough a semiconductor device, according to an embodiment. In aparticular embodiment, the semiconductor device is the semiconductordevice 300 described with reference to FIG. 3. In step 510, a portion ofa current path is selected within the semiconductor device. In anembodiment, the portion of the current path selected is in the form of aconductive lead or bond wire that has a predefined resistance. Anexample of a conductive lead wire may include the conductive pathbetween the Kelvin sense pin 340 and the input pin 310 described withreference to FIG. 3. The conductive lead wire has a predefinedresistance that has less variation and is independent of semiconductorproperties of the semiconductor device compared to the on resistance. Instep 520, current is sensed by measuring voltage across the conductivelead wire using Kelvin current sense techniques.

Various steps described above may be added, omitted, combined, altered,or performed in different orders. In a particular embodiment, anadditional step 430 may be added to open the high-side switch 220 andturn on the low-side switch 230 in response to detecting an over currentcondition. In step 530, a load current path is interrupted when thecurrent sensed is greater than a predefined threshold.

Although illustrative embodiments have been shown and described, a widerange of modification, change and substitution is contemplated in theforegoing disclosure and in some instances, some features of theembodiments may be employed without a corresponding use of otherfeatures. Those of ordinary skill in the art will appreciate that thehardware and methods illustrated herein may vary depending bn theimplementation. Accordingly, it is appropriate that the appended claimsbe construed broadly and in a manner consistent with the scope of theembodiments disclosed herein.

1. A semiconductor device comprising: an input pin to receive an input;an output pin coupled to a first side of a comparator; a control pin toreceive a control signal, wherein the control signal controls a flow ofcurrent between the output pin and the input pin; and a Kelvin sense pinelectrically coupled between a die of the semiconductor device and theoutput pin and also coupled to a second side of the comparator fordetermining a voltage drop across the outpin pin, whereby the voltagedrop is used to control the flow to current from the input pin to theoutput pin.
 2. The device of claim 1, wherein the semiconductor deviceis one of a bipolar junction transistor (BJT), an insulated gate bipolartransistor (IGBT), a metal-oxide semiconductor field effect transistor(MOSFET), a gate turn-off thyristor (GTO), a mosfet controlled thyristor(MCT), a silicon controlled rectifier (SCR), and a junction field effecttransistor (JFET). 3.-8. (canceled)
 9. The device of claim 1, whereinfunctions of the input pin and the output pin are reversed.
 10. Asemiconductor device comprising: an input pin to receive an input; anoutput pin coupled to a first side of a comparator; an control pin toreceive a control signal, wherein the control signal controls a flow ofcurrent between the output pin and the input pin; and a Kelvin sense pinelectrically coupled between a die of the semiconductor device and theoutput pin and also coupled to a second side of the comparator fordetermining voltage drop across the output pin, wherein a layout of theinput pin, the output pin and the control pin is in accordance with an8-pin small outline (SO8) integrated circuit (IC) footprint, and whereinthe SO8 footprint is modified by including the Kelvin sense pin as a9^(th) pin.
 11. A semiconductor device comprising: an input pin toreceive an input; an output pin coupled to a first side of a comparator;a control pin to receive a control signal, wherein the control signalcontrols a flow of current between the output pin and the input pin; anda Kelvin sense pin electrically coupled between a die of thesemiconductor device and the output pin and also coupled to a secondside of the comparator for determining voltage drop across the outputpin, wherein packaging for the input pin, the output pin and the controlpin is in accordance with a flip-leaded molded package (FLMP), andwherein the FLMP footprint is modified by including the Kelvin sense pinas a 6^(th) pin.
 12. A semiconductor device comprising: an input pin toreceive an input; an output pin coupled to a first side of a comparator;a control pin to receive a control signal, wherein the control signalcontrols a flow of current between the output pin and the input pin; aKelvin sense pin electrically coupled between a die of the semiconductordevice and the output pin and also coupled to a second side of thecomparator for determining voltage drop across the output pin; andwherein the comparator is a differential amplifier to receive a firstinput from the Kelvin sense pin and a second input from the output pin,wherein the differential amplifier provides an output indicative of thecurrent.
 13. A method for sensing current flowing through asemiconductor device, the method comprising: selecting a portion of acurrent path within the semiconductor device, wherein the portion of thecurrent path has a predefined resistance, wherein the predefinedresistance is independent of semiconductor properties of thesemiconductor device; and measuring voltage across the portion of thecurrent path to sense the current.
 14. The method of claim 13,semiconductor device is one of a bipolar junction transistor (BJT), aninsulated gate bipolar transistor (IGBT), a metal-oxide semiconductorfield effect transistor (MOSFET), a gate turn-off thyristor (GTO), amosfet controlled thyristor (MCT), a silicon controlled rectifier (SCR),and a junction field effect transistor (JFET).
 15. The method of claim13, the predefined resistance has a lower variance compared to avariance of an internal semiconductor on (SON) resistance that isdependent on the semiconductor properties.
 16. The method of claim 15,wherein the lower variance provides an improved accuracy of sensing thecurrent compared to an accuracy of sensing the current with the SONresistance.
 17. The method of claim 13, wherein a flow of an outputcurrent provided to a load coupled to the device is interrupted when avalue of the current is greater than a predefined value.
 18. Aninformation handling system (IHS) comprising: a processor; a powersupply having a semiconductor device, the power supply operable toprovide power to the processor, wherein the semiconductor deviceincludes: an input pin to receive an input; an output pin coupled to afirst side of a comparator; a control pin to receive a control signal,wherein the control signal controls a flow of current between the outputpin and the input pin and wherein the power is interrupted when a valueof the current is greater than a predefined value; and a Kelvin sensepin electrically coupled between a die of the semiconductor device andthe output pin and also coupled to a second side of the comparator fordetermining voltage drop across the output pin. 19.-20. (canceled)